The present invention relates to a linear motor.
Japanese Patent Application Laid-Open Publication No. 119919/2001 (Patent Document 1) discloses a linear motor including a stator constituted by a pair of inductors and a moving element constituted by an armature. The pair of inductors is formed of a magnetic material. Each pair of inductors includes a tooth row constituted by a plurality of teeth provided at a predetermined pitch τ in a moving direction of the moving element. The armature includes an armature iron core, at least one permanent magnet row, and a plurality of armature windings. The armature iron core includes at least one opposed surface facing the tooth row and is constituted by a plurality of steel plates laminated in a direction orthogonal to the moving direction of the moving element. The permanent magnet row is constituted by a plurality of permanent magnets. The permanent magnets are provided on the opposed surface at a pitch τ/2 in the moving direction of the moving element and are so arranged that different polarities alternately appear along the opposed surface. The armature windings are wound around the armature iron core and are arranged side by side in the moving direction of the moving element.
In the conventional linear motor, however, the armature windings are arranged side by side in the moving direction of the moving element. Thus, a lot of armature windings (18 windings in the case of the linear motor disclosed in the Patent Document 1) become necessary. Further, the steel plates are laminated in the direction orthogonal to the moving direction of the moving element, thereby constituting the armature iron core. Accordingly, the armature iron core and a member for supporting the armature iron core must be secured by screws and the like that pass through the steel plates. Manufacture of the linear motor is thereby complicated and requires much time and effort.